Class Items

Would help with champion balance, because you could actually give classes tools they need instead of giving them to everyone. For example, you could buff adc items so that they would be more relevant, in current state, if you buff ad items, they will be adopted by top lane bruisers ( i.e. fiora/darius/camille) I've seen this mentioned before and flamed to death and I understand why, BUT, for the sake of better balance I think this is a viable option. Thoughts?